The present invention relates to a micro component reactor module useful with a hydrogen generation system that provides a source of hydrogen for a fuel cell. Hydrogen fuel cells are non-polluting and highly efficient power sources (e.g., FUEL CELLS GREEN POWER, Los Alamos National Laboratory, U.S. Department of Energy. (1999) that are being developed for use in automotive, mobile and personal use applications having predetermined power output requirements where mobile, convenient, safe and compact power units are required.
It is an object of the invention to provide a water gas shift (WGS) reactor module for a process used to produce hydrogen gas for powering a fuel cell used in the foregoing applications.
It is an object of the invention to provide a reactor module for a gas processing unit operation in a hydrogen generation system used with a fuel cell or fuel cell stack. In a preferred embodiment, it is an object to provide a reactor module useful with a steam reforming process that generates hydrogen for powering hydrogen fuel cells in automotive, mobile, personal use and other predetermined discrete power requirement applications.
It is a further object to provide a reactor module that may be ganged in parallel, or provided in a battery of units, to provide an assembly in which total aggregate output is a multiple of the individual units assembled.
In the invention, one or more heat exchangers and a chamber block with open volumes (or chambers) capable of being charged with a catalyst are assembled in a modular unit that includes an inlet and an outlet for reactant products. The chamber block includes one or a plurality of longitudinal cavities (chambers) that may be filled with a catalyst through which fluid flow is directed. Micro channel heat exchangers having laminar fluid flow pathways are aligned in the unit to provide operative interconnection to the catalyst filled chambers (catalyst chambers) in the chamber block. An enclosure having appropriate inlet and outlet orifices for the components defines a modular assembly used in a stage of the hydrogen producing/fuel cell system.
In the invention, the reactor catalyst filling the chamber may be a powder and/or particulate with a nominal particle size ranging from about 125 microns to about 3 millimeters. In general, catalysts useful in the invention include those composed of mono-, bi-, and poly-metallic alloys and oxides of IIIB including rare earth metals and the noble metals and transition metal groups. Other groups include the alkali metal families IA, IIA and IVA and Sb, Te, Bi, and Se.
The chamber block cavities charged with catalyst form a micro-component reactor; the overcall catalyst volume, and in turn, the number of chambers and their dimensions which determine chamber block size, for a given power specification may be differently configured.
In the operation of an embodiment, the reactor temperature is in the design range of approximately 250 degrees Celsius to approximately 650 degrees Celsius and reactant flow is at a predetermined pressure of less than approximately 3 atmospheres. Individual reactor modules may be sized for fuel cell systems with capacities such as 0.65 kW, 1.25 kW, or 5 kW. Reactor modules may be interconnected in gangs or batteries to form modules in which the reactant product flows of individual units are exhausted through a common orifice.
The invention is described more fully in the following description of the preferred embodiment considered in view of the drawings in which: